Electric throttle control



March 5, 1940. H NORMAN ET AL 2,192,714

ELECTRIC THROTTLE CONTROL 7 Filed May 20, 1937 6 SheetsSheet 1 f f 7a 58 LE6 T,

March 5, 1940. NORMAN AL 2,192,714

ELECTRIC THROTTLE CONTROL Filed May 20, 1937 6 Sheets-Sheet 2 March 1940- H. M. NORMAN ET AL 2,192,714

ELECTRIC THROTTLE CONTROL Filed May 20, 195'! s Sheets-Sheet s March 5, 1940- H. M. NORMAN ET AL 2,192,714

m ncwnxc THROTTLE CONTROL Filed May 20, 1937 6 Sheets-Sheet 4 March 5, 1940- I H. M. NORMAN ET AL 2,192,714

ELECTRIC THROTTLE CONTROL I Filed-May 20, 1957 6 Sheets-Sheet 5 Mamh 5, 1940- H. M. NORMAN ET AL ELECTRIC THROTTLE CONTROL Filed May 20, 1957 6 Sheets-Sheet 6 ll w NQ/K/ 5% m %\w @k% wm m 9% Patented Mar. 5, 1940 UNITED STATES 2,192,714 ELECTRIC THROTTLE CONTROL Horace M. Norman, Willard H. Farr, George E.

Coxon, Thorolf Paul,

Chicago,

ginia and Arden W. Le Fevre,

Ill., assignors to Stewart-Warner Corporation, Chicago, 111.,

a corporation oi Vir- Application May 20, 1937, Serial No. 143,862

16 Claims.

This invention relates to electric throttle controls, and more particularly to an electric. means for controlling the throttle valve of an automobile.

The throttle valve of an automobile is'ordinarily under the control of the operator by means of an accelerator pedal and hand throttle, both of which are connected to the carburetor throttle valve by mechanical linkage. A disadvantage of this system is that when engines are placed at the rear of the vehicle, as is now being done, especially in buses and in some pleasure cars, this mechanical linkage becomes increasingly diflicult to incorporate into the automobile in a satisfactory manner.

To be efilcient the throttle control system of an automobile should respond readily to slight pressure on the throttle and should be smooth and sure in operation. The system should be free from rattles and should obstruct as little as possible the servicing of the automobile.

An object of this invention is to provide a mechanism in which the foot and hand throttle controls actuate the throttle of the carburetor through an electrical system.

Another object is to provide a carburetor control system in which the accelerator pedal gives full control of the engine speed independently of the hand throttle setting. 7

Another object is to provide a carburetor control that requires very little pedal pressure and is smooth in operation regardless of the placement of the engine in the vehicle.

A further object is to provide a carburetor control in which slight displacement during a portion of its stroke will cause a relatively great change of resistance in the control circuit while at a different part of its stroke a large displacement of the control will cause a relatively small change of resistance.

A further object is to provide an electric speed governor that is especially adapted to be incorporated into an electric throttle control system, but with certain modifications may be used with a mechanical throttle control.

Another object is to provide means in an electric throttle control for cutting out the influence of the hand control when the foot control is depressed.

Afurther object is to prevent burning of the several contact points in an electric throttle control system.

A further object is to provide a throttle valve actuating torque motor that has substantially straight line torque characteristics.

Other objects and advantages of this invention will become apparent from the following description which relates to a preferred embodiment of this invention.

In the accompanying drawings, forming a part of this specification, and in which like numerals are employed to designate like parts throughout the same,

Figure 1 is a diagrammatic representation of a preferred embodiment of the control device shown connected to a throttle valve;

Figure 2 isa vertical section of the foot control unit;

Figure 3 is a sectional view of the device shown in Figure 2 taken in the direction of the arrows along the line 3-3 of Figure 2;

Figure 4 is a sectional view of the device shown in Figure 2 taken in the direction of the-arrows along the line 4-4 of Fig. 2;

Figure 5 is a side plan view of an alternative resistance unit to be used in the device shown in Fig. 2; Y

Figure 6 is a front plan view of the hand throttle control unit;

Figure '7 is a side plan view of the device shown .in Fig 6;

, Figure 8 is a top plan view of the throttle valve shifting torque motor;

Figure 9 is a side plan view of the torque motor shown in Fig. 8;

Figure 10 is an end plan view of the torque motor shown in Figures 8 and 9;

Figure 11 is a sectional view of the torque motor shown in Figures 8, 9 and 10 taken in the line l|-ll of Fig. 10;

Figure 12 is a sectional view of the torque motor shown in-Figs. 8, 9, 10 and 11 taken in the direction of the arrows along the line l2-l2 of.

Fig. 11;

Figure 13 is asectional view of a detail of the torque motor taken in the direction of the arrows along the line l3-|3 of Fig. 11;

Figures 14, 15, 16, and 1'7 are circuit diagrams for alternative" control devices according to this invention;

Figure 18 is a diagrammatic representation of an alternative throttle valve control device;

Figure 19 is a circuit diagram showing the sending unit of an electrical speed governor connected with the electric throttle control circuit;

Figure 20 is a longitudinal sectional view of a sending unit of an electric speed governor according to this invention;

Figure 21 is a fractional view partly in section of a modification of the device shown in Figure 20;

Figure 22 is a longitudinal partial sectional view of a receiving unit of an electric speed governor adapted to be used with a mechanically controlled throttle valve. It is shown diagrammatically connected to a sending unit such as shown in Fig. 20;

Figure 23 is a view partly in section in the direction of the arrows along the line 23-43 of Fig. 22.

Referringtol'ig.1ofthedrawingr.inwhich isshown a mu representation of an embodiment of the invention, the electric throttle control system consists of a torque motor 8| linked to the carburetor throttle valve 82 by means oi the arm 83 and link 24. Connected to this torque motor is an electric circuit including a battery it, commonly suppiied'with the automobile, a hand throttle control 82, and a foot control ll. In this instance the loot control, Figs. 2, 3 and 4, consists of a foot pedal 42, pivoted on a hinge ll connected to the iioor board ll of the automobile.

The upper end of the pedal is provided with a depending stop ll, and the floor board with a similar stop 40. when the pedal is depressed. these stops are brought together and limit the motion of the foot pedal. Fastened to the lowerside of the foot pedal is a depending arm IO, which passes through a hole I2 in the floor board, and is provided at its lower end with a hole II. A coil spring 8| surrounds the arm II and presses with its ends against the floor board ll and pedal 42, thereby moving the pedal 42 upwardly when the foot pressure is released. Through the hole I a bushing 56 is secured to the arm II by means of the nut 58. The bushing It is provided with an axial hole it through which extends a rod 2, the upper half of which is cut away at II to a smaller diameter, and passes through a hole It iltted thereto in the upper end of the bushing It.

In the space 88 between the inside end of the bushing 10 and the annular ridge 12 on the rod 62 and surrounding the shaft M, is a coil spring II which urges the lower end of the rod I2 outwardly from the bushing. The upper end of the rod 82 is provided with a button Ii that limits its outward movement during the assembly or disassembly of the unit. The lower end of the rod is riveted at It to a roller carrying bracket II.

Th s bracket consists of two U-shaped metal stampings riveted together at their central portions to form a member of H-shaped section. The outwardly projecting fingers ll of this bracket are provided with aligned holes .2, through which passes a shaft ll. As shown in Fig. 3, this shaft carries two rollers 20, the peripheries of which have a thinner section than the hubs.

The upper arms 88 of the H-shaped bracket serve as guides and are in slidable relation to the lower section I. of the bushing 56. This lower section 90 is squared so that the bracket and rollers are free to move inwardly and outwardly against the pressure of the spring II, but are prevented from rotational movement.

Positioned adjacent the rollers II is a resistance unit 92, which consists of a block ll built up of several thicknesses of insulating material. The surface of the block adjacent the wheels II is of arcuate shape so that as the pedal is depressed and the bracket and wheels attached thereto are moved downwardly in an arc, the spring 14 will urge the wheels '6 into contact with the resistance unit throughout the travel of the pedal 42. Wound around the insulating block 94 is a coil of resistance wire 96, connected at one end to the binding post 98 and at the other end to the binding post ill. These binding posts 98 and "II also serve to secure the resistance unit 92 within the box-shaped case "2. The upper post 98 is insulated from the case I02 by means of the insulating sleeve Ill and washer I", while the lower post III is similarly insulated bythesleeve Ill andwashcr III.

thereto at the top the binding post ill. The upper post It is insulated from the bar 2 by the sleeve Ill while the lower post Ill serves as an electrical connection for the bar 2 and is insulated from the case I02 by the sleeve-lit and the washer lit. A- spring strip I2. is secured to the bracket It and is resiliently held in contact with the inside suriaceofthebar H2. Itwilibeseen thatasthe rollers it are moved upwardly and downwardly by the pedal 42, the spring ll urges the rollers into contact with the resistance coil It, the ends of which are connected to the binding posts OI and III, while the third binding p0 Ill makes contact with the rollers thrcughthe bar "2 and spring strip l2l.

The resistance coil II is tapered, being larger at its upward end than at the lower end, therefore, since each turn of the coil near its upward end is longer than a similar turn farther down on the resistance unit, it will be seen that the depression of the pedal a unit distance near the upward end of its stroke will cause a greater change of resistance in the circuit than will a similar movement of the pedal farther down in its stroke. The advantage in using this tapered resistance unit is that it causes a more even deilection of a carburetor valve opening torque motor, to be later described, in proportion to the deflection of the foot pedal 42. v

Figure 5 shows an optional resistance unit that may be used in place of the tapered unit .2, if it is desired to secure a constant change of resistance throughout the stroke of the pedal l2. In this imit all of the turns I22 are of substantially the .same size. instead of being graduated as are those of the unit 92.

In some of the embodiments of the device to be pointed out later an insulating post I24 secured inside the case "2 supports a pair of spring strips I28 provided with contact points I22. These strips are insulated from each other and from the case, and are normally at rest with the contact points I28 separated, thereby breaking a circuit across the leads I and I12. An insulating strip IN is secured to the lower surface of the lower strip I28. The upper surface of the bushing it is provided with an upwardly extending finger I" which engages the insulating strip I22 and urges the two contact points l2. together when the pedal 42 is in its upward position, thereby closing the circuit across the leads I II and I32. How these leads Ill and I32 are utilined in a control system will be pointed out later.

The hand throttle control, best shown in Figs. 6 and 7, comprises a sub-panel I a secured to the rear side of the automobile instrument panel I by nuts I and bolts I42. A resistance coil I is wound on a tapered block I which is secured to the sub-panel I38 by screws and nuts numbered Ill and I" at the large end and IE2 and ill at the small end, and is insulated therefrom by the fiber washers it, I" and I".

A shaft "2 extends through aligned holes I and I" in the subpanel I28 and instrument panel Ill and is provided with a reduced portion Ill carrying a thrust washer III which bears against the front surface of the sub-panel and limits the inward movement of the shaft. On the back side of the sub-panel I the shaft I62 has a threaded portion "2 of still smaller diameter on which are placed in order, a spacing bushing I'll which rests against the shoulder I",

a spring finger I18 provided with a contact butsembly thereon inwardly, thereby allowing rotation of the shaft I62 by the knob I88 secured thereto at the outer end by the set screw I98, but still providing sufiicient friction to retain the shaft I62 and spring finger I18 at any desired setting.

A contact button I92 secured to the back surface of the spring contact finger I18 rests against an arcuate contact member I94 which is bent under at the end and secured to the screw I48.

The screw I48 also serves as a binding post to connect this member I94 into an electrical cir cult. The screw I52 at the other end of the resistance block I46 is connected to the small end of resistance coil I44 and serves as a binding post therefor.

It will be seen that if the binding posts I48 and I52 are connected in an electrical circuit, the resistance of the circuit may be varied by turning the knob I88.

The torque motor 38 illustrated in detail in Figs. 8 to 13 is provided with a magnetic flux conducting field I96 built up of a plurality of laminated sheets I98 secured between the end plates I99 and 28I by the rivets 284. The laminated sheets I98 are rectangular in shape with a central opening which is cut away at the ends to provide an unobstructed space 288 with arcu ate pole pieces 2I8. Thev end housings 288 and 282 are secured to the end plates I99 and 28I by screws 283 and have central openings provided with bearing bushings 2I2 and 2I4 through which extends an armature shaft 2 I6 to which is secured an armature core 2I8 between the pole pieces 2I8. The armature core is of the well known H type and is provided with a coil 228 of insulated wire wound thereon, the ends of which are brought out through the pig tails 222 and 224. These pig tails, which have an insulating covering, are connected to the binding posts 228 and 228, one of which, 228 is insulated from the end housing by the insulating bushing 238 and washer 232. The ends of the shaft 2 I6 where they pass through the bushings 2I2 and 2I4 are cut away to a smaller diameter to provide shoulders 234 and 236 which act as thrust bearings against the inner ends of the bushings 2I2 and 2I4 to limit endwise motion of the shaft and armature 2I8.

A helical spring 238 is coiled around the right hand end of the motor shaft 2 I6 as seen in Fig. 11, and is attached at its inner end to a collar 248 secured to the shaft 2I6 by the set screw 242. The other end of the spring 238 is secured by a screw 243 in a slot 244 provided in a square post 246 which is secured to the motor end housing 282 in any suitable manner such as by welding. By means of this spring 238 the armature 2I8 is biased in a clockwise direction as seen in Fig. 10.

Secured to the collar 248 by means of the pin 248 is a fiat member 258 with two outstanding arms 252 and 254 perpendicular to each other. These two arms serve as stops operating against the post 246 to limit the degree of rotation of the armature 2I8 and shaft 2I6. As shown, one of these arms, 252, is provided with a screw 256 extending therethrough to serve as an adjustment for setting the position the armature 2I8 will take when 'unenergized.

The other end of the shaft 2 I6 is provided with an arm 258 secured thereto by the set screw 268.

The arm 258 has on one side of the shaft 2I6 a plurality of holes 262 any one of which may be used to connect the link 34 (Fig. 1) which links with the carburetor throttle valve 32 through the arm 33. Which one of these holes 262 is to be used depends upon how muchmovement is required'of the link 34, since the holes 262 farther from the shaft 2I6 will give greater movement than those near the hub. On the other side of the shaft 2I6 (Fig. 9) the arm 258 may be provided with an adjustable counterbalance weight 264 held in place by the set screw 266. This weight may be moved on the arm 258 to a position which gives a proper balance to the reciprocating parts thereby providing smoother operation in thedevice.

When the armature is unenergized, it comes to rest with its poles canted with respect to the field poles 2 I8, so that when energized, it will always start to rotate in a clockwise direction as seen in Fig. 12. Notice also that the field poles 2I8 are specially shaped, so that the gap between the entering edge of the armature and the field becomes progressively larger for greater movement of the armature. That is, the gap at v268 is greater than the gap at 218. This is done so as to give torque changing characteristics in the motor opposite to those in the spring 238, thereby giving the armature a dead beat action when the current therethrough is quickly increased or decreased.

In Fig. 1, the torque motor 38 is shown with its arm 258 connected to the carburetor valve 32 by the rod 34 and arm 33. The terminal 226 is grounded while the other terminal 228 is connected through the hand throttle control 38 to one of the contacts I28 by the conduits 212, 214 and 216. The conduit 212 also is connected to the roller 86 of the foot control by conduit 218 and to the large end of the resistance unit 92 through a high resistance unit 288 and conduit 282. The other contact point I28 is connected to the small end of the resistance unit 92 by the conduit 284 and to the ground through the conduit 284, an automobile ignition switch 286, and the battery 36.

In operation when the ignition switch is on and both the foot and hand controls are in the idling positions, no current will flow through the circuit excepting for a small amount that is able to leak through the circuit comprising the motor 38, conduit 212, high resistance 288, conduit 282, resistance unit 92, conduit 284, switch 286 and battery 36. The small amount of current that flows in the above circuit is not sufficient to energize the motor 38, nor to cause any appreciable wastage, consequently, the throttle valve 32 remains closed.

If the hand throttle 38 is opened somewhat, the motor 38 is energized through conduits 212 and 214, variable resistor 38, conduit 216, switch points I28, conduit 284, switch 286 and battery 36. As the resistance 38 is decreased, the flow of current becomes greater and motor 38 is more highly energized thereby producing more torque coil 82, thereby energizing the motor 88 through the conduits 212 and 218, roller 86 coil 82, conduit 284, ignition switch 286 and batteryv 86. As the pedal 42 is depressed further the resistance in the circuit will be lowered and the motor 88 further energized.

The high resistance unit 288 is used in the above and other circuits to prevent arcing of the several contact points which would otherwise take place if the circuit through the motor 88 were completely broken.

.In the circuits shown in Figs. 14 and 15, the current flowing through the motor 88 at any time depends upon the combined setting of both the hand and foot controls. these two circuits the one shown in Fig. 14 is the easiest to construct, since the movable arms 18 and "8 of the resistance units may be grounded, however, in this case both terminals of the motor 88 must be insulated instead or only one as shown in the detailed drawings of the motor. cult (Fig. 15) has the advantage that it the conduits on the motor side or the resistance units 88 and 48 become grounded, the motor will become deenergized, while if the same thing takes place in the device shown in Fig. 14, the motor will become fully energized and open the throttle valve wide.

In both these circuits the two variable resistanee units 38 and 48. are in parallel with each other and in series with the motor", ignition switch 286 and battery 86. The diflerence between them lies in the fact that in the device illustrated in Fig. 14, the motor is connected through the battery 86 to ground while in Fig. 15 the motor is connected directly to ground.

In both of the above circuits the switch with the contact points I28 is not used in the foot control and the movable coil contacting elements 86 and I88 are designed to still be in contact with the end of their respective coils when in idling position.

In the device illustrated in Fig. 16 as in those shown in Figs. 14 and 15, the current in the motor 38 depends upon the combined setting of both the hand and foot throttles, and diflers from those circuits in utilizing the high resistance coil 288, thereby making it possible to reduce the current to a minimum in idling position without burning the contact points by repeated arcing.

In this circuit both variable resistors 88 and 48 are designed to allow the contacting members 86 and I88 to run oil the end of their respective coils when in idling position. The hand control variable resistor 88 is connected in series with the motor 38, ignition switch 286 and battery 38, while the small end of the foot control coil 48 is connected between the motor 88 and hand control 38. The large end or the foot control coil is connected through the high resistance 288 to ground, while the coil contacting wheel 88 is grounded directly.

In idling position the only current in the motor 88 is that which flows through the high resistance 288, resistance unit 82 and motor 88 all in series. The amount 01' current thus flowing is not suillcient to energize the motor 88 nor to place any appreciable drain on the battery 88.

If the hand controlled resistor. "is moved so that the contacting member I18 touches the coil I44, the current flow is through the battery 86, motor 38, resistance unit I44, contacting member I18 and thence to the ground. If the hand control 88 is left in idling position and the foot control is depressed so that the wheel 86 touches the The other, cirresistance coil 82, the current flow is then through the battery 86, motor 88, resistance unit 82, contacting member 86, arm 18, and thence to the ground. A further movement of either arm 18 or I18 to the left as shown in Fig..16 will cause a lowering of the resistance in the motor circuit, and since the two resistors 88 and 48 are in parallel, the resistance of the motor circuit and hence the current flowing therethrough will depend upon the combined setting of the two resistors.

In the device illustrated in Fig. 17 like the one shown in Fig. 1, the foot control 48 is designed to regulate the current in the motor 88 independ ently of the hand throttle setting. This system operates without the use of the switch contact points l28shown in Figs. 1 and 2, but requires instead that the hand resistor 38 have a third binding post 288 connected to the large end or the resistance coil .I44, and that the foot control 48 be provided with a contact strip 288 adjacent the large end of the coil, but insulated therefrom, which makes contact with the wheel 86 when the foot throttle is released.

The small ends of the two resistance coils 82 and I44 are connected together and thence through the ignition switch 286 and battery 36 to ground. The large end of the hand control resistance unit I44 is connected through the binding post 288, high resistance 288, and motor 88 to ground. The movable coil contacting member I18 of the hand control is connected to the strip 288 at the end 01' the foot control resistance unit 82, while the foot control movable coil contacting wheel 86 is connected between the motor 88 and high resistance 288.

In the above device when both throttle controls 38 and 48 are in the idling position, the flow of current through the motor 38 is very slight and is through the battery 36, ignition switch 286, hand control coil I44, high resistance unit 288 and motor 88 all in series. If the hand throttle control is advanced, the motor is energized through the battery 36, ignition switch 286, coil I44, coil contacting element I18, strip 288, wheel 86,- arm 18 and motor 88. If is depressed, the wheel 86 is moved from the strip 288 to the coil 82 thereby cutting out the hand control 88 and energizing the motor through the battery 86, switch 286, coil 82, wheel 86, am 18 and motor 88.

It will be seen from the above that the torque motor 38 is under the influence of the hand control 38 until the foot pedal is depressed, at which point the hand control is cut out of the motor circuit and all control taken over by the foot control 48.

An adjustable stop 282 may be provided in con nection with the hand control to provide a means for temporarily setting the idling adjustment from the automobile dash board. Ordinarily, this stop282 will be retracted and is supplied only for emergency use.

The device illustrated in Fig. 18 is provided with a foot control which uses a well known carbon pile resistance unit in a box 284. The motor current is supplied from the battery 86 through now the foot pedalthe ignition switch 286, carbon pile in the box In operation the motor current during idling operation flows through the battery 36, ignition switch 286, carbon pile in the box 284, high resistance 286 and motor 36. When the pedal 42 is depressed, the switch 238 is closed and the motor current then fiows from the battery 36 through the ignition switch 286, carbon pile in the box 284, switch 238 and motor 36, thus energizing the motor with the carbon pile in series, so that further depression of the pedal 42 lowers the resistance of the circuit and thereby produces greater torque in the motor 36.

The speed governing means comprising a part of this invention consists of a speed responsive resistor 366 (Figs. 19, 20 and 21) which is shown as connected in series with the torque motor and a control circuit similar to the one illustrated in Fig. 1. It should be understood, however, that this governor may be connected in a like manner in any of the foregoing circuits.

Although many forms of speed responsive variable resistors may be used in this manner; the one here shown and described is of the magnetic type and consists of a slider 362 which moves over a resistance coil 364under the influence of the rotating magnet 386.

The mechanism of this speed responsive resistor comprises a die casting 368 carrying a magnet shaft 318 rotatably journalled therein. This magnet shaft has a suitable gear 312 which meshes with and is driven by the gear 3 which is usually mounted on the transmission end of the propeller shaft of the vehicle. The die casting 388 has a neck 316 which extends into a suitable opening provided in the transmission housing 318, the assembly being held in place by a clamp 328 which engages a flange 322 provided by the die casting. This flange serves the further purpose of preventing the entry of dirt ormoisture into the opening in the transmission housing 3 I 8 in which the extension 3 l 6 is located.

The upper end of the magnet shaft 3l8 has affixed thereto a cup-shaped magnet support 324 to which is attached a permanent magnet 386 bent into the form of an annulus but having its ends separated by a gap, which may either be left open or which may be filled with non-magnetic material, as desired.

Surrounding the magnet 366 and spaced therefrom is an iron field plate 326 which forms a strong magnetic field between itself and the magnet 386. In this space is located'a speed cup 328 formed of aluminum or other suitable material. This speed cup 328 is mounted on a shaft 338 which has one end journalled in a jeweled bearing 332 carried by the upper end of the iron field plate 326. This jeweled bearing 332 insulates the shaft 338 from the field plate 326. The other end of the shaft 338 rests upon a jewel 334 which carries the weight of the shaft 338 and speed cup 328 when the governor mechanism is assembled in normal operating position with the shaft 338 substantially vertical and the jewel 334 at the lower end thereof. A second jewel 336 forms a guide for the shaft 338 and restricts the lateral movement thereof. Both of the jewels 334 and 336 are located in a housing 338 carried by a combined bearing support and oil shield 348, which is made of brass or other non-electromagnetic material. A screw 342 permits adjustment of the jewel 334 and is locked in adjusted position by a nut 344.

The shaft 338 carries the slider 382 which moves over the resistance384 mounted for rotation in the upper end of the iron field plate 326.

One end of this resistance coil 384 is brought out through a slot 346 in the iron field plate 326 and by means of a pig tall 348, stud 358, and spring 352 is in electrical communication with a terminal 354. p

The terminal 354 is carried by the upper end of a cover 356 which is attached to the die casting 366 by screws 358. The cover 356 may be of any suitable material, such as iron, and the terminal 364 is insulated therefrom by insulating discs 368. 362 and 364.

A nut 366 and metal washer 368 clamp the terminal 354, spring 352, insulating discs 368, 362

and 364 to the upper end of the cover 356. A second nut 318 clamps in place one of the electrical conduits 312 in the governor circuit.

the speed cup 328 in the same direction. This rotation of the speed cup, together with its shaft 338 and slider 382 is resisted by a spring 314, which has one end attached to the shait 338 and a second end secured to a post 316. The post 316 and stud 358 are both mounted on overhanging ends of an insulating plate 316 riveted to the upper end of the field plate 326. The slider 382 and shaft 338 are in electrical communication with the post 316 through spring 314 and also through a contact member 388, which bears lightly against the upper endof the shaft 338. When the governor mechanism 388 is mounted with the shaft 33min vertical position, this contact member 388 and the weight of the shaft itself and the speed cup 328 suffice to hold the lower end of the shaft 338 against the jewel 334, but where it is desired to so position the governor mechanism that the shaft 338 is not in this vertical position, it is to be understood that a second jewel similar to the jewel 334 will be utilized to limit longitudinal movement of the shaft 338.

The post 316 is electrically connected to a second terminal 382 through a spring 384. This post 316 is insulated from the cover 356 in the same manner in which the post 354 is insulated from this cover. Attached to the post 382 is one end of a wire 386 which connects the slider 382 into the governor circuit.

The annular resistance unit 384 is provided with a threaded boss 388 into which is screwed an adjusting pin 338 extending through slots 382 and 384 in the field plate 326 and cover 356. The pin 388 has an annular slot 336 which engages a spring strip 398 that acts as a cover for the slot 334 and as a frictional element to secure the adjusted setting of the pin 388. This pin 388 is used to rotate the resistance unit 384 and thereby determme the speed to which the governor will limit the vehicle by regulating the degree of movement of the slider 362 before it comes in contact with the coil of the resistance unit 384. g

The cover 356 has an annular shoulder 39!! which is located above a similar shoulder provided by the iron field plate 326. Between these two shoulders is clamped a corrugated spacing ring 488-provided with inwardly directed fingers 482 which accurately locate the spacing ring 488. By means of this structure, the cover 356 clamps in place on the base of the die casting 388 the iron field plate 326, and this field plate in turn overlies the outwardly directed flange 484 formed at the lower end of the bearing support 348 whereby the latter is also clamped against the base of the die casting 388. The cover 356, iron field plate 326, bearing support 348 and shaft 338 with its associated speed cup 328, can all be removed by simply unscrewing the screws 358 and ill The rotation of the magnet 386 tends to rotate pin 390. This structure greatly simplifies assembly of the mechanism when it is originally manufactured and also facilitates inspection and repair.

The governor as described, since it is driven from the transmission, will limit the top speed of the vehicle, but will not prevent rapid acceleration in the lower gears.

If it is desired to limit the vehicle to a certain motor speed regardless of road speed, then the governor unit should be driven from the motor. One means for accomplishing this is shown in Fig. 21, in which a motor generator pulley 433 is secured to the generator shaft 400 by means of an internal threaded section 4l0 on the end of the magnet carrying shaft 3I0. The threaded section 0 serves as a securing member for the pulley in place of the nut supplied with the vehicle and also as a means for driving the governor from the generator shaft. A bracket 2 fastenedat one end to some convenient member of the vehicle motor supports the generator by means of the screws 4 which extend therethrough into the governor flange 322.

In operation the foot throttle or hand throttle 38 may be opened, thereby increasing the current through the motor 30 and opening the carburetor throttle valve. As the car speed increases, the slider 302 will be moved over the resistance unit 304 until the additional resistance added to the torque motor circuit will cause a partial deenergization of the motor 30 and a partial closing of the carburetor throttle valve, thereby limiting the top speed of the vehicle.

In Figs. 22 and 23 is shown a means for connecting the electric governor to a throttle valve controlled by mechanical linkage. The governor unit 300 is similar to the one above described excepting that here as an increase in engine speed moves the slider 302 over the resistance unit 304, resistance is removed from thegovernor circuit instead of being added thereto. This is accomplished by connecting the opposite end of the resistance unit 304 to the terminal post 354.

The throttle valve control unit consists of a throttle control rod 6 provided with a slidable collar 8 having two oppositely projecting pins 420 and 422. The pin 420 engages a slot 424 in the end of a carburetor valve control rod 423, while the pin 422 engages a similar slot 420 in the end of an oppositely extending rod 430. The rod 430 is pivotally mounted near its center 432 by a screw 434 extending therethrough into a bracket 436. Pivoted to the lower end of the rod 43 is a link 438 which is connected at its opposite end to the torque motor 30. A coil spring 440 is positioned around the control rod 6 with one end bearing against the collar 4i! and the other end against an adjustable collar 442 secured to the control rod M6 by the set screw 444.

In operation, a movement of the throttle control rod 416 to the right as seen in Fig. 22 also moves the collar 8 through the spring 440..

This movement of the collar 8 opens the carburetor valve through the arm 426 and rotates the armature in the torque motor 30 through the arm 430 and crank bar 438. When the engine speed rises above a predetermined point, the governor 300 will reduce the resistance of the circuit by means of the slider 302 moving over the resistance unit 304, thereby energizing the torque motor 30 from the battery 35, This energlzation rotates the armature of the torque motor 30 which moves the bar 438 to the right thereby moving the collar 8 to the left against the springulandpartiallyclosingtheearburetor throttle valve, thus, limiting the speed of the vehicle to the predetermined point.

The carburetor valve is closed by the helical spring446securedtothepost443 atoneendby the screw 450 and attached at its other end to the arm 426, when the control rod 4| is returned to idling position.

The foregoing detailed description has been given for the purpose of clearness of understanding only, and no unnecessary limitations should be understood therefrom.

Having described our invention, what we claim as new and useful and desire to protect by Letters Patent is:

1. An electric carburetor throttle control comprising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature, and hand and foot control means for varying the current in said armature means, said foot control means cutting out the influence of the hand control means.

2. An electric carburetor throttle control comprising the combination of a throttle valve. armature means for shifting said valve, means for supplying current to said armature, hand and foot control means for varying the current in said armature means, and means for incorporating a high resistance in the armature circuit when both the hand and foot controls are retarded.

3. An electric carburetor throttle control comprising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature means, and hand and foot control means for varying the current in said armature, the current in said armature being determined by the setting of both the hand and foot controls coniunctively.

4. 1m electric carburetor throttle control comprising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature, hand and foot control means for varying the current in said armature, the foot control comprising a resistance unit in series with the armature means and the current supply means through a high resistance, a pedal actuated slider on said resistance unit in shunt with the high resistance, the hand control comprising a variable resistor in shunt through a switch with the first said resistance unit and the high resistance.

5. An electric carburetor throttle control com prising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature, hand and foot control means for varying the current in said armature, and the hand and foot controls comprising variable resistors in shunt with each other and in series with the current supply and arms.- ture.

6. An electric carburetor throttle control comprising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature, hand and foot control means for varying the current in said armature, the hand and foot controls comprising variable resistors in shunt with each other and in series with the current supply and armature, and the free end of one of the variable resistances being grounded through a high resistance.

7. An electric carburetor throttle control comprising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature, hand and 73 foot control means for varying the current in said armature, the hand control comprising a resistance unit in series with the current supply means and the armature means through a high resistance, a slider on said resistance unit; the foot control comprising a separate resistance unit having a connection at one end, the other end being free, a contact strip near the free end and insulated therefrom, a slider to move over the last said resistance unit and contact strip, the contact strip connected to the hand control slider, and the last said resistance unit and slider being bridged across the hand control resistance unit and high resistance in series.

8. An electric carburetor throttle control comprising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature, foot control means for varying the current in said armature means, said foot control means consisting of one or more pedal actuated rollers, and said rollers operating to contact difierent portions of a resistance unit depending on the degree of depression of the pedal.

9. An electric carburetor throttle control comprising the combination of a throttle valve, armature means for shifting said valve, means for supplying current to said armature, hand and foot control means for varying the current in said armature means, said foot control means consisting of one or more pedal actuated rollers, said rollers operating to contact different portions of a resistance unit depending on the degree of depression of the pedal, a switch adjacent the said resistance unit, the pedal in its extended position operating to close said switch, and said switch when closed adapted to complete a circuit comprising said current supply means, said armature means and said hand control and when open to interrupt the last said circuit.

10. In an electric throttle control system including a circuit with hand and foot control means therein, a throttle valve, electric torque means for shifting the valve, means for supplying current to said torque means, said control means serving to vary the current in said torque means;

said torque means comprising a wound armature.

positioned to rotate within a flux conducting field, resilient means normally to position the poles of the armature canted with respect to the poles of the field, and electrical connections from the armature to the control circuit.

11. In an electric throttle control system including a circuit with hand and foot control means therein, electric torque means for shifting a throttle valve, means for supplying current to said torque means, said control means serving to vary the current in said torque means; said torque means comprising a wire wound armature positioned on a shaft to rotate within a flux conducting field, said armature shaft having stops to limit the arc of rotation of the armature, resilient means normally to position the poles of the armature canted with respect to the poles of the field, the tension of the resilient means and one of the stops being adjustable, electrical con nections to the ends of the armature, and an adjustable connection between the armature shaft and the throttle valve.

12. In an electric throttle control system including a circuit with hand and foot control means therein, a throttle valve, electric torque means for shifting the valve, means for supplying current to said torque means, said control means serving to vary the current in said torque means;

said torque means comprising a wound armature positioned to rotate within a flux conducting field, resilient means normally to position the poles of the armature canted with respect to the poles of the field, each of said field poles being asymmetrical, and electrical connections from the armature to the control circuit.

13. In an electric throttle control system including a circuit with hand and foot control means therein, a throttle valve, electric torque means for shifting the valve, means for ,supplying current to said torque means, saidcontrol means serving to vary the current in said torque means; said torque means comprising a wound armature positioned to rotate within a flux conducting field, resilient means normally to position the poles of the armature canted with re-' spect to the poles of the field, the distance between the armature and field poles being less at-the entering edge of the field than at the leaving edge, and electrical connections from the armature to the control circuit.

14. An electric carburetor throttle control comprising the combination or a throttle valve, armature means for shifting said valve, means for supplying current to said armature, and hand and foot contol means for varying the current in said armature means, said foot control means operative to vary the current in said armature means independently of the setting of said hand control means, and said hand control means operative to vary the current in said armature means only when said foot control means is in substantially one position.

15. In an electric throttle control system including a circuit with hand and. foot control means therein, electric torque means for shifting a throttle valve, means for supplying current to said torque means, said control means serving to vary the current in said torque means; said torque means comprising a flux conducting field, an armature positioned to rotate within said fiux conducting field, resilient means normally to position the poles of the armature canted with respect to the poles of the field, and the poles of said torque means being shaped so that the torque curve of said torque means and the torque curve of said resilient means will cross at substantially right angles whereby a dead beat action is provided.

16. In an electric throttle control system including a circuit with hand and foot control means therein, an electric torque means for shifting a throttle valve, means to supply current to said torque means, each said control means comprising a variable resistor having a slider and a resistance unit to vary the current in said torque means, said torque means comprising a flux conducting field, an armature positioned to rotate within said field, resilient means normally to position the poles of the armature canted with respect to the poles of the field, the poles of said torque means being shaped so that the torque curve of said torque means and the torque curve of said resiiient means will cross at substantially right angles, and each said variable resistor having a tapered resistance unit so proportioned that the ratio between the movement of the slider and the change of motor speed is substantially constant throughout the range of the resistor.

HORACE M. NORMAN. WILLARD H. FARR. GEO. E. COXON. 'I'HOROIF PAUL. ARDEN W. LE mm. 

